The present invention relates to a metering and conveyor arrangement for liquid to be mixed, with several associated delivery pumps being actuated by a drive unit.
Such metering and conveyor arrangements are used, for example, in machines for the production of reaction foam synthetic materials. In order to ensure a perfect chemical reaction of the liquids, the quantities and the mixing ratio must be metered very accurately before being joined in the mixing unit. There are known low-pressure conveyor arrangements where displacement piston pumps are fastened to swiveled trapezoidal holding elements with regulable stroke. The load volume is set via the stroke. The desired mixing ratio is maintained by displacing the pump cylinders parallel to each other so that the basic stroke of the drive unit has different effects on the individual pistons.
The productivity of such an arrangement is relatively small since after each load, the pistons must be moved back to draw in new material. Also, the setting of the mixing ratio is inaccurate and time-consuming and not possible without special tools.
Accordingly, it is an object of this invention to provide a metering and conveyor arrangement of the above-described type which is especially suited for small load quantities and which can be quickly and precisely adjusted without tools.
Another object of the invention is the labor saving and cost reduction resulting from its use.
A further object of the present invention is to provide an arrangement, as described, which is substantially simple in construction, may be economically maintained and serviced, and has a substantially long operating life.